The only difference between a shuttle run and mass production is whether your chip is repeated 100 times in different parts of the wafer (surrounded by other people's chips) or a few thousand times completely covering the wafer with copies of just your chip.

The manufacturing process is identical either way.

Interesting fact, the term tape out comes from the way chips were physically laid out back in the early days. The chip layout was manually arranged using pieces of coloured tape on a large workspace/table. Once complete, this was photographed a layer at a time, which was then optically reduced to create the mask sets for manufacture. We still use the term tape out today, but no tape involved. I would love to have an experience of designing back during those days, it's so hands on.

a "tape out" is the process of transforming a design into a physical die - i.e. a manufacturing run. It's when you hand over a design to a foundry to do their thing with it.